Commercial HVAC systems

Question 1

In commercial hvac systems, there are two types of HVAC systems

Answer 1

Constant air volume (CAV)
Variable air volume (VAV)

Question 2

In a simple constant air volume system, the supply air flow rate is (…)?

Answer 2

Is constant, but the supply air temperature is varied to meet the thermal loads of a space.

Question 3

What does most CAV systems serve

Answer 3

Small and serve a single thermal zone.

Question 4

What does CAV stands for

Answer 4

Constant Air Volume

Question 5

The two types of CAV systems that are commonly used to modify the supply air temperature?

Answer 5

The terminal reheat system
The mixed air system

Question 6

Disadvantage of terminal reheat system.

Answer 6

Waste energy

Question 7

Mixed air volume system.

Answer 7

Has two air streams, one for the coldest and one for the hottest. The two air streams are strategically combined to offset the space load .

Question 8

Hot and cold air never mixes in the three-deck system. (True or False)

Answer 8

True

Question 9

What is the difference between a multi zone system and a three deck multi zone system ?

Answer 9

Unlike the multi zone system, a three deck multi zone system a neutral air stream that is neither cooled or heated. In this system the cool and hot air never mixes, eliminating energy waste !

Question 10

Where does the air mixing occur in a dual duct system?

Answer 10

In the zone or close to the zone it is serving

Question 11

Where does the air mixing occur in a multi zone system?

Answer 11

Mixing occurs in the air handling unit.